Thanks for the link to crown boilers. It had the information i was looking for for converting linear to sq foot load.

So this keystoker is more than enough, heck i can even add another zone or two. Which will be great, because want to put a 25x30 addition on house in a few years, with lots of windows(greenhouse effect) on southern side. Family room that has a lot of outdoors in it from windows, leading on to deck. i have about 250 sq ft load output to use for this. This wont be maxing out boiler specs , it includes an 10% overage for load output.